1. Field of the Invention
The present invention relates generally to lift seats and, more particularly, to an improved lift seat which assists a user in rising from and descending to a position on the floor.
2. Description of the Prior Art
Lift seats have been described in the prior art; however, none of the prior art devices disclose the unique features of the present invention.
In U.S. Pat. No. 6,430,761, dated Aug. 13, 2002, Brandorff, et al., disclosed an improved portable patient transfer device comprising a small wheeled base having a vertically disposed telescoping lifting column extending upwardly therefrom. A patient support means extends from the column to support the patient. A crank, accessible to both patient and attendant, is used to raise and lower the lifting column for transfer between surfaces with different heights, such as beds, wheelchairs, and car seats. The lift may be closed and temporarily attached to a wheelchair for convenient transport with a patient. The lift is small and lightweight and may be easily transported and stored. The lift is further economical to manufacture.
In U.S. Pat. No. 6,185,761, dated Feb. 13, 2001, Chapman, et al., disclosed a system for raising a person lying on the ground which includes a lifting seat comprising a back rest coupled to a seat portion. At either side of the back rest and seat portion t here are provided side supports. The system is such that in use it can be slid onto a person lying on his/her side, rotated such that the back rest lies on the ground, with the supports supporting the person during rotation to a back-lying position. The back rest can then be rotated upwardly to bring the person into a sitting position.
In U.S. Pat. No. 6,161,232, dated Dec. 19, 2000, Von Schroeter, et al., disclosed an invalid lifting device comprising a first mast upstanding from a first elongate chassis member and a second mast upstanding from a second elongate chassis member which is parallel or substantially parallel to the first chassis member. The lifting device also comprises a lifting arm supported by and extending between the first and second masts, the lifting arm comprising two parts pivotable relative to one another so that the distance between the masts can be varied. One part is supported by the first mast and the other part is supported by the second mast. Power operated means are provided for moving the two chassis members towards and away from one another. Each part of the lifting arm comprises a parallelogram linkage to maintain the chassis members in parallel or substantially parallel relationship as the two chassis members are moved towards and away from one another. Each mast may be telescopically extendible/retractable and power operated means may be provided for extending and retracting the two masts in synchronism with one another.
In U.S. Pat. No. 6,389,619, dated May 21, 2002, Dunn disclosed an invalid lifting device which includes a mobile chassis, a lifting mechanism and a sling connectible to the arm supports to assist in raising a seated person to a standing or substantially standing position. The lifting mechanism includes a lifting arm and an actuator device operative to raise and lower the lifting arm. The lifting arm is pivotable about first and second horizontal axis. The lifting mechanism also includes guiding elements defining a guide path along which the second horizontal axis is caused to move as the actuating device raises and lowers the lifting arm.
In U.S. Pat. No. 5,421,639 dated Jun. 6, 1995, Bartholomew disclosed a portable, storable lifting device for invalids. The device includes a jack base having a backwardly inclined jack upright on which is mounted a jack platen including a hook. Forward and rearward facing wheeled legs are provided attached to the jack base. Each forward facing leg is hinged to the jack base through a universal joint thereby allowing the legs to be folded into a compact position for transportation or storage. A segmented lever is provided. A folding seat is provided having a back hinged to a bottom. Strap means are attached to the seat bottom and to the seat back for securing to the seat both the upper and lower torso of a fallen invalid who is positioned prone on a floor surface. The seat includes dual function means attached to the back, both for using the segmented level to provide leverage to the seat, whereby the prone invalid is rotated to an upright sitting position, and for engaging the jack hook, whereby the seat containing the prone invalid is raised above the floor with the invalid in an upright sitting position.
In U.S. Pat. No. 4,399,572, dated Aug. 23, 1983, Johansson disclosed a seat comprising a carrier frame mounted on a hoisting gear and support means extending between outwardly directed carrier frame portions. Since the seats at patient-lifting devices often become very dirty, they need to be cleaned in special cleaning devices, so called decontamination devices. However, the present seats are not suitable for cleaning in cleaning devices of this type and time-consuming measurements are required to loosen and reengage the seats. In order to eliminate said problems and provide a seat that may be cleaned in especially efficient cleaning devices and further may be quickly and safely disconnected and connected in a simple manner the seat according to the invention is characterized by the features that the carrier frame comprises two separate sitting means spaced from each other to provide a seat with an opening therein, whereby each sitting means and/or the carrier frame has a coupling device adapted to permit fixing of the sitting means above the support means by moving the sitting means into engagement with the carrier frame and whereby each sitting means and/or carrier frame has a position indicator arranged such that any one from above may determine whether the sitting means is in fixed position above the support means.
While these lift seats may be suitable for the purposes for which they were designed, they would not be as suitable for the purposes of the present invention, as hereinafter described.